Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753840AbaFUP6K (ORCPT ); Sat, 21 Jun 2014 11:58:10 -0400 Received: from mail-pa0-f49.google.com ([209.85.220.49]:50466 "EHLO mail-pa0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752772AbaFUP6I (ORCPT ); Sat, 21 Jun 2014 11:58:08 -0400 Date: Sat, 21 Jun 2014 21:27:59 +0530 From: Himangi Saraogi To: Jean-Christophe Plagniol-Villard , Tomi Valkeinen , linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: julia.lawall@lip6.fr Subject: [PATCH] drivers/video/fbdev : dereference without an error test Message-ID: <20140621155758.GA4741@himangi-Dell> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org After a variable is assigned the result of backlight_device_register, an error test should be performed before a dereference. A simplified version of the semantic match that finds this problem is as follows: // @def0@ expression x; position p0; @@ x@p0 = backlight_device_register(...) @protected@ expression def0.x,E; position def0.p0; position p; statement S; @@ x@p0 ... when != x = E if (!IS_ERR(x) && ...) {<... x@p ...>} else S @unprotected@ expression def0.x,E; identifier fld; position def0.p0; position p != protected.p; @@ x@p0 ... when != x = E * x@p->fld // Signed-off-by: Himangi Saraogi Acked-by: Julia Lawall --- drivers/video/fbdev/omap2/displays-new/panel-sony-acx565akm.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/video/fbdev/omap2/displays-new/panel-sony-acx565akm.c b/drivers/video/fbdev/omap2/displays-new/panel-sony-acx565akm.c index c7ba4d8..acd9ff1 100644 --- a/drivers/video/fbdev/omap2/displays-new/panel-sony-acx565akm.c +++ b/drivers/video/fbdev/omap2/displays-new/panel-sony-acx565akm.c @@ -817,6 +817,10 @@ static int acx565akm_probe(struct spi_device *spi) bldev = backlight_device_register("acx565akm", &ddata->spi->dev, ddata, &acx565akm_bl_ops, &props); + if (IS_ERR(bldev)) { + r = PTR_ERR(bldev); + goto err_reg; + } ddata->bl_dev = bldev; if (ddata->has_cabc) { r = sysfs_create_group(&bldev->dev.kobj, &bldev_attr_group); @@ -862,6 +866,7 @@ err_reg: sysfs_remove_group(&bldev->dev.kobj, &bldev_attr_group); err_sysfs: backlight_device_unregister(bldev); +err_reg: err_detect: err_gpio: omap_dss_put_device(ddata->in); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/